powerpc/watchdog: Improve watchdog lock primitive

[karo-tx-linux.git] / arch / powerpc / kernel / watchdog.c

diff --git a/arch/powerpc/kernel/watchdog.c b/arch/powerpc/kernel/watchdog.c
index b67f8b03a32d0f12ce29eeb4ac3be0a97384fe72..fda4d044d3264508b93e163978e336d1d188eef4 100644 (file)
--- a/arch/powerpc/kernel/watchdog.c
+++ b/arch/powerpc/kernel/watchdog.c
@@ -71,15 +71,20 @@ static inline void wd_smp_lock(unsigned long *flags)
         * This may be called from low level interrupt handlers at some
         * point in future.
         */
-       local_irq_save(*flags);
-       while (unlikely(test_and_set_bit_lock(0, &__wd_smp_lock)))
-               cpu_relax();
+       raw_local_irq_save(*flags);
+       hard_irq_disable(); /* Make it soft-NMI safe */
+       while (unlikely(test_and_set_bit_lock(0, &__wd_smp_lock))) {
+               raw_local_irq_restore(*flags);
+               spin_until_cond(!test_bit(0, &__wd_smp_lock));
+               raw_local_irq_save(*flags);
+               hard_irq_disable();
+       }
 }
 
 static inline void wd_smp_unlock(unsigned long *flags)
 {
        clear_bit_unlock(0, &__wd_smp_lock);
-       local_irq_restore(*flags);
+       raw_local_irq_restore(*flags);
 }
 
 static void wd_lockup_ipi(struct pt_regs *regs)